Amantadine (Solution) Instructions for Use

Marketing Authorization Holder

Ecofarmplus, JSC (Russia)

ATC Code

N04BB01 (Amantadine)

Active Substance

Amantadine (Rec.INN registered by WHO)

Dosage Form

Amantadine

Solution for infusion 0.4 mg/1 ml: 250 ml or 500 ml fl., 1 pc.

Dosage Form, Packaging, and Composition

Solution for infusion colorless, transparent.

Excipients: sodium chloride – 9 mg, water for injections – up to 1 ml.

250 ml – glass bottles (1) – cardboard boxes.
500 ml – glass bottles (1) – cardboard boxes.

Clinical-Pharmacological Group

Antiparkinsonian drug – glutamate NMDA receptor blocker

Pharmacotherapeutic Group

Antiparkinsonian agent

Pharmacological Action

Antiparkinsonian and antiviral agent, a tricyclic symmetrical adamantanamine.

It blocks glutamate NMDA receptors and thereby reduces the excessive stimulatory effect of cortical glutamate neurons on the neostriatum, which develops against the background of dopamine deficiency. Amantadine inhibits NMDA receptors of substantia nigra neurons, reduces the entry of Ca²⁺ into them, which reduces the possibility of destruction of these neurons. It has a greater effect on stiffness (rigidity and bradykinesia).

It inhibits the penetration of influenza A virus into the cell.

Pharmacokinetics

After oral administration, it is completely absorbed from the gastrointestinal tract. C_max in blood plasma is reached after 5 hours. It is excreted in the urine. T_1/2 of amantadine sulfate is 12-13 hours, unlike amantadine hydrochloride, whose T_1/2 is 30 hours.

Indications

Parkinson’s disease, parkinsonism syndrome (rigidity, tremor, hypokinesia).

Neuralgia in herpes zoster caused by the Varicella zoster virus.

Prophylaxis (including in combination with vaccination) and treatment of influenza A.

ICD codes

Dosage Regimen

Administer the solution by intravenous infusion only. Do not administer as a bolus injection.

For the treatment of Parkinson’s disease and parkinsonism, infuse a dose of 200 mg (equivalent to 500 ml of the 0.4 mg/ml solution) once daily. Infuse the total volume over exactly 3 hours using a controlled infusion device.

For influenza A prophylaxis, administer 200 mg once daily or divide into two doses of 100 mg each. For influenza A treatment, initiate with a single 200 mg dose or 100 mg twice daily.

For herpes zoster neuralgia, the standard dose is 100 mg twice daily. A single daily dose of 200 mg may be used if tolerated.

Adjust the dosing frequency based on renal function and patient tolerance. For patients with creatinine clearance below 50 ml/min, reduce the dose or increase the dosing interval.

Initiate therapy at lower doses for geriatric patients and those receiving concomitant antiparkinsonian drugs to minimize adverse effects.

The maximum daily dose for all indications should not exceed 400 mg administered by intravenous infusion. Monitor for efficacy and signs of toxicity, particularly central nervous system effects.

Adverse Reactions

From the central nervous system headaches, depression, visual hallucinations, motor or mental agitation, convulsions, irritability, dizziness, sleep disorders, tremor, mental disorders accompanied by visual hallucinations, decreased visual acuity.

From the cardiovascular system development or worsening of heart failure, orthostatic hypotension; rarely – arrhythmia, tachycardia.

From the digestive system rarely – anorexia, nausea, constipation, dry mouth.

From the urinary system in patients with prostatic hyperplasia – difficulty urinating; polyuria, nocturia.

Dermatological reactions dermatosis, appearance of a bluish coloration of the skin of the upper and lower extremities (livedo reticularis).

Contraindications

Hepatic insufficiency, chronic renal failure, psychoses (including in history), thyrotoxicosis, epilepsy, closed-angle glaucoma, prostatic hyperplasia, arterial hypotension, chronic heart failure stage II-III, state of agitation, predelirium, delirious psychosis, first trimester of pregnancy, lactation period, simultaneous use of triamterene and hydrochlorothiazide, hypersensitivity to amantadine.

Use in Pregnancy and Lactation

During pregnancy, the use of amantadine is possible only for strict indications and under medical supervision. Contraindicated in the first trimester of pregnancy.

If it is necessary to use during lactation, the issue of discontinuing breastfeeding should be decided.

Use in Hepatic Impairment

Contraindication: hepatic insufficiency.

Use in Renal Impairment

Contraindicated in chronic renal failure. Use with caution in patients with impaired renal function.

Geriatric Use

Use with caution in elderly persons.

Special Precautions

Use with caution in patients with impaired renal function, with simultaneous use with other antiparkinsonian agents, as well as in elderly persons. In such cases, correction of the amantadine dosing regimen is required. In patients with hyperreflexia, treatment should be discontinued gradually.

Information on the effectiveness of amantadine for reducing extrapyramidal disorders during treatment with antipsychotic agents (drug-induced parkinsonism) is contradictory.

Do not consume alcohol during treatment.

Effect on ability to drive vehicles and mechanisms

During the treatment period, one should not engage in activities requiring high concentration of attention and rapid psychomotor reactions.

Drug Interactions

With simultaneous use, an increase in the side effects of antiparkinsonian agents is possible.

With simultaneous use with thiazide diuretics, the possibility of developing toxic effects of amantadine (ataxia, agitation, hallucinations) cannot be excluded, probably due to a decrease in its renal clearance.

A case of acute confusion in an elderly patient with simultaneous use with co-trimoxazole has been described.

With simultaneous use with quinine, quinidine, a decrease in the excretion of amantadine in the urine is possible.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.